1. Field of the Invention
The present invention relates to an electrical connector assembly, and more particularly to an ultra low profile electrical connector assembly of which an insulative housing integrally formed with a shielding shell.
2. Description of the Prior Art
EIA, Electrical Industries Association, releases a Standards Proposal No. 3652-A, Proposed New Specification "Detail Specification for Trapezoidal Shielded Connector 0.8 mm Pitch Used with Very High Density Cable Interconnect (VHDCI)". According to FIG. 10 on page 10, two trapezoidal shielded female connectors are stacked in a mirror-image arrangement. In addition, the trapezoidal mating portions are not located centrally with respect to their housing. In FIG. 40 on page 29, a male connector mated to the female connectors is shown. In order to have two male connectors fit to the stacked female connectors, the island and the shroud portions are offset from a central line thereof.
U.S. Pat. Nos. 5,761,805 and 5,766,033 issued to Guyer and Davis disclose method for making a high-density and high-density connector, respectively. The connectors disclosed meet the requirements set in the above mentioned Standards. After the connector housing (12) is terminated with conductive wires (24, 22), an over-molding process will be performed to enclose a plastic layer over the connector housing (12). Since the mating portion (14) is offset arranged, the bottom wall (64) of the shell member (14) will become a critical point during the over-molding process.
According to the actual practice, for the reason of easy molding the thickness of the plastic layer (P) over the bottom wall (64) of the shell member (14) shall at least for 1.00 mm, as shown in FIG. 1. This also provides enough rigidity to sustain external impact. However, when the bottom wall (64) of the shell member (14) is offset to accommodate the connector housing (12), the plastic layer deployed over the bottom wall (64) is reduced to 0.6 mm rendering the over-molding process over the bottom wall (64) becomes extremely difficult in light of the plastic flow within such a tiny gap between the bottom wall (64) and an inner wall of the mold cavity, as shown in FIG. 2. In order to inject the molten plastic through the 0.6 mm gap, injection pressure have to increase and the manufacturing cost is increased inevitably. In addition, even the thin layer is finally formed, it is vulnerable to external impact and can not provide any protection. Many efforts have been applied to overcome this problem and none of them is acceptable.
U.S. patent application Ser. No. 09/404,441 filed on Sep. 22, 1999 by the same assignee as the instant application, discloses that an upper and lower metallic shells are integrally molded with an upper and lower plastic covers of a connector wherein at least a portion of one of the upper and lower shells protruding over the corresponding cover. The instant application is a continuation-in-part of the U.S. patent application Ser. No. 09/404,441, which adopts the similar principle to lower the profile/height of an entire connector like a RJ series connector.
U.S. Pat. Nos. 4,497,526, 4,647,136, 4,703,991, 4,786,259, 4,878,848, 4,878,858, 4,915,655, 5,035,641, 5,118,312, 5,378,172 and 5,702,271 indicate a prior low profile RJ connector which extends beyond a notch of a circuit board in a half-height thereof, or/and is diminished in the thickness of a wall of a plastic housing to form a cutout where a latch of a mating plug extends through. However, the lowered-profiles of these connectors are insufficient in applying with a thinner electrical device like a PCMCIA card for computer.
U.S. Pat. Nos. 5,183,404, 5,336,099, 5,338,210, 5,411,405 and 5,547,401 disclose another low profile RJ connector perpendicularly attached into the PCMCIA card. However, the vertical insertion of the RJ plug inside the RJ connector causes a protruded outgrowth of the entire assembled PCMCIA card.
U.S. Pat. Nos. 5,248,267, 5,562,504, 5,660,568, 5,773,332 and 5,938,480 disclose another low profile RJ connector which horizontally receives a mating RJ plug therein. The lowered profile of the RJ connector is still insufficient and lacks an EMI protection.